Method of making return-bends.



C. H. TRUE & C. A. W. BRANDT. METHOD OF MAKING RETURN BENDS'.

APPLICATION FILED MAR. 24, 1911. L55, fl; Patented Feb. 5, 1918.

2 SHEETS-SHEET I Patented Feb. 5, 1918.

2 smssrs-suasr 2 fi/ d/Yfl/ vwawIozS klbtoz'nc x APPLICATION FILED MAR. 24. I91?- (3. H. TRUE & c. A. W. BRANDT. METHOD OF MAKING RETURN BEND S.

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tartan CHARLES H. TRUE, 015 HAMMOND, INI'JIA'NA. AND CARL A. W. BRA'NIF'K, 01 It'itlfif NEW YORK, ASSIGNORS TO LOtZDMO'IIV'E SU'JPEBHEATER COMPANY, 431 NEW ll fimri,

N. 1., A COBP QRELTION OF DELAWARE.

METHOD OF MAKING- RETURNBENDS.

Specification of Letters Patent.

Patented lt elo. 5, rate.

Application filed March 24, 1917. Serial No. 157,237.

To all whom it may concern:

Be it known that we, Crrannes H. TRUE, a citizen of the United States, residing at Hammond, Indiana, and CARL A. W. Baum, likewise a citizen of the United States, residing at Bayside, New York, have invented certain new and useful Improvements in Methods of Making Return-Bends, of which the following is a specification.

Our invention relates, as just stated, to the art of making return bends. More particularly it relates to the art of making that type of return bends in which the end portions of the two pipes to be joined are themselves fashioned into such a return bend. so that the return bend and the two pipes joined by it all constitute one integral structure.

There are perhaps other ways of making such return bends, but the one On which the present invention constitutes an improvement is one described in Patents 1.153.110 and 1.169.200. both granted jointly to C. ll. True and N. T. iftchiee. The latter of these two patents sets forth in detail particularly the first part of the process, which results in an incomplete bend, one specific way of completing it. being described in the former patent. The present invention starts with the incomplete pipe bond as made by the process of Patent 1,109,200 or its equivalent, but in completing the structure departs in some material respects from the method described in 1,155.110.

The object of the present invention may then be stated as the providing of an improved method of closing and shaping the end of a return bend of the class referred to.

The invention will be readily understood from the following description which is to be read in connection with the accompanying drawings. In these drawings Figure 1 represents an incomplete return bend of the kind to which the present method is to be applied; Fig. 2 represents an end view of the same. and Fig. 3 a section taken axially through both pipes; Fig. 4 represents, in section, the incomplete bend after the present process has been partly performed on it; .lfiig. 5 being an'cnd view of the same; Figs. 0, 7 and 8 show the bend after the process has been carried a step farther, Fig. 7 showing also, in section, the two dies in which the process is performed. Fig. 0 shows the bend in. the press about to be given its final shape. Figs. 10 11, and 12 are views of the completed bend, Fig. ll being a sectional view taken on line ll li of Fig. 10 looking toward the left, while Figs. l3, l4 and 15 are views of a modifies. tion of the final form, Fig. 14. being a sec tional 'ViQW taken on line li-d-t of Jig. 13, looking; toward the left.

The incomplete bend illustrated in Figs. 1, 2 and 8 is seen to comprise two pipe ends united. for a certain distance from their ends by a transverse passage. The walls of this passage have been made from the material of the pipes themselves by the process de scribed in Patent 1,109,200, referred to above. The pipe bend is incomplete, the pipes and connecting passage being; still open at the end as shown.

la the process for closing; the bond as described in Patent 1,155,110 and ashithorto practised, the first step is the insertion of a specially shaped tool into the open end of the bend, givingthe bend a shape merging gradually from circular at the open and into the more or less nearly elliptical sec-- tioii near the bottom of the connecting channel. For certain reasons thisstep is objec tionable and the present method eliminates it. instead of inserting; such an. expanding member the open end of the incomplete bend is heated and given a circular contour by blows delivered at the appropriate portions on the outside o'l the bend near its end, viz. at and near the points designated by the reference numerals l. The resultant, shape is illustrated in l igs. i and 5. The blows that force the portions 1 inwardly at the same time force the portions at. and about points 2 (mtwardly, so that the en treme end is given a circular form. This preliminary shaping can be done by means separate and dillercnt from. the means used for the next succeeding step or it may be doneby the same means and in such, a

wav that the two really form one continuous and single operation. Y

The drawing down or swaging of the end to a point as shown in. Figs. 6, i", and 8 is preferably done on a rotary swaging machine. The form of this well-known type ot machine need not be here described. lit is sutliciont tosay that in it two symmetricaldies 3 and d of Fig. '2', whose eilectire stirtaees are the taiwaterpart the shape it re:

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views of the bend are desired to give the end of the return bend, alternately close and open in the direction toward and from the axis AB, at the same time rotating about this axis. The mecha nism is such that there are eight or ten opening and closing movements per revolntion, though the machine may be modified to give some other number. The two dies are shown in Fig. 7 in their closed or innermost position. The incomplete pipe bend 's firmly clamped in some feeding device of any prefered construction after having first been raised to a forging heat. It is then moved toward and into the die. As it enters farther and farther the end is swaged down to conform to the interior surface of the die, finally assuming a shape such as shown in Fig. 7. The portions designated by reference numeral 2 in Fig; 2- have simultaneously bulged outward so that the other as shown in Figs. 6 and 8. The die is made with an axial hole 5, into which any excess of metal can eX- trude, as at 6. This excess can be removed later on if desired. The present method, it will be noticed, does away with the final welding formerly necessary, since no cleft or opening of any kind is left at the end of the bend after the swaging operation, the excess of metal just spoken of being really a solid pieceof metal without any aXial opening whatever.

The bend is now a completely operative article, but for certain purposes it is objectionable to have the portions marked 7? protrude beyond the two imaginary parallel lanes tangent to both pipes. To bring t. =1 portions within these limits the bend is heated and then placed in a press, diamatically indicated in Fig. 9. The cfi/ surfaces of this press are so shaped the form given to the bend is that shown in Figs. l0, l1, and 12. This part of the process may he done in one or in several stages, as desirec. In the latter case as many sets of dies will be used as there are stages, each set approaching the desired finished form more closely, up to the last set,

which is the precisecounterpart of the form the bend is to have If desirech the bend. can, by giving the effective surfaces ofthe press the proper contour be given some other shape, such as that illustrated in Figs. 13, 1 1, and 15, where a section on line 14-1 is fi-shaped. This completed form, it will be noted particularly from Figs. ll. 12, 14c and 15, has no portions of its walls extending beyond the limits spoken of above, and its external appearance dill'ers in no material respect from the form of the completed bends described in the two patents hereinabove referred to.

It is manifest that certain variations are possible without departing from the spirit of the claims.

What we claim is 1. The process of completing a pipe bend of the class referred to which comprises applying pressure on its outside near the open end so as to give the end a circular contour, swaging down said end so it is closed, and finally shaping said bend.

2. The process of completing a. pipe bend of the class referred to which comprises applying pressure on its outside near the open end so as to give the end a circular contour, swaging down the bend so it is closed and a part of the metal adjacent to the end forms a relatively short solid bar, removing a portion of this bar, and finally shaping said bend.

3. The process of completing a pipe bend of the class described which comprises delivering blows on the appropriateportions of the outside thus closing the end to a substantially conically shaped point, portions of the structure extending beyond the parallel planes tangent to both pipes; and then flattening the bend until said portions lie within said parallel planes.

l. The process of completing a pipe bend of the class described which comprises shapingit by blows on the appropriate portions of its outside so as to give its end a circular contour, swaging it down so that it is closed and a certain amount of the metal adjacent to the end is in the form of a relatively short, solid, cylindrical piece and that portions of the pipe bend extend beyond the parallel planes tangent to both pipes, removing a part of the solid cylindrical piece, and flattening the end until all portions lie within said planes.

CHARLES H. TRUE. CARL A. W. BRANDT.

Witnesses for C. H. True:

C. A. Massimo, H. R. THOMPSON. Witnesses for C. A. W. Brandt:

JAMES K. Sco'rr, B. R. BRISTOL. 

